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所以我有一個時間選擇器全部設置好了,它在我的應用程序中打開得很好。我可以選擇時間,點擊'完成',它就像它應該的那樣關閉。我現在想要輸入時間並將其顯示在XML文件中定義的TextView中。無法顯示用戶輸入的時間
我已經得到了這樣做是使用這行代碼最接近:
TextView textView = (TextView)getView().findViewById(R.id.timeOfWorkoutTextView);
此代碼至少不顯示在Eclipse的錯誤,但我每次運行應用程序和打'完成'按鈕,它會引發錯誤並關閉應用程序。下面是logcat的:
04-27 19:13:49.482: E/AndroidRuntime(11553): FATAL EXCEPTION: main
04-27 19:13:49.482: E/AndroidRuntime(11553): java.lang.NullPointerException
04-27 19:13:49.482: E/AndroidRuntime(11553): at com.example.test_project.TimePickerFragment.onTimeSet(TimePickerFragment.java:30)
04-27 19:13:49.482: E/AndroidRuntime(11553): at android.app.TimePickerDialog.tryNotifyTimeSet(TimePickerDialog.java:130)
04-27 19:13:49.482: E/AndroidRuntime(11553): at android.app.TimePickerDialog.onClick(TimePickerDialog.java:115)
04-27 19:13:49.482: E/AndroidRuntime(11553): at com.android.internal.app.AlertController$ButtonHandler.handleMessage(AlertController.java:166)
04-27 19:13:49.482: E/AndroidRuntime(11553): at android.os.Handler.dispatchMessage(Handler.java:99)
04-27 19:13:49.482: E/AndroidRuntime(11553): at android.os.Looper.loop(Looper.java:137)
04-27 19:13:49.482: E/AndroidRuntime(11553): at android.app.ActivityThread.main(ActivityThread.java:5059)
04-27 19:13:49.482: E/AndroidRuntime(11553): at java.lang.reflect.Method.invokeNative(Native Method)
04-27 19:13:49.482: E/AndroidRuntime(11553): at java.lang.reflect.Method.invoke(Method.java:511)
04-27 19:13:49.482: E/AndroidRuntime(11553): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:792)
04-27 19:13:49.482: E/AndroidRuntime(11553): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:555)
04-27 19:13:49.482: E/AndroidRuntime(11553): at dalvik.system.NativeStart.main(Native Method)
04-27 19:13:51.060: I/Process(11553): Sending signal. PID: 11553 SIG: 9
我打算使用的StringBuilder創建一個包含小時和分鐘的字符串,然後使用這樣的:textView.setText(hourMinuteString);
這裏是我的所有代碼:
package com.example.test_project;
import java.util.Calendar;
import android.app.Dialog;
import android.app.DialogFragment;
import android.app.TimePickerDialog;
import android.os.Bundle;
import android.text.format.DateFormat;
import android.view.View;
import android.widget.TextView;
import android.widget.TimePicker;
public class TimePickerFragment extends DialogFragment
implements TimePickerDialog.OnTimeSetListener {
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Use the current time as the default values for the picker
final Calendar c = Calendar.getInstance();
int hour = c.get(Calendar.HOUR_OF_DAY);
int minute = c.get(Calendar.MINUTE);
// Create a new instance of TimePickerDialog and return it
return new TimePickerDialog(getActivity(), this, hour, minute,
DateFormat.is24HourFormat(getActivity()));
}
public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
TextView textView = (TextView)getView().findViewById(R.id.timeOfWorkoutTextView);
}
public void showTimePickerDialog(View v) {
DialogFragment newFragment = new TimePickerFragment();
newFragment.show(getFragmentManager(), "timePicker");
}
}
我非常新的Android開發人員和編程一般,所以一些非常詳細的,愚蠢的,足以換一個孩子理解的答案將不勝感激!!!!
在此先感謝!
嘗試你的建議後,所以我仍然得到同樣的NullPointerException異常錯誤...玩了一個小時,仍然沒有得到它! – 2013-04-28 19:27:00
究竟哪一行是例外?您可以使用新的StackTrace更新您的問題修改代碼和LogCat – iTech 2013-04-28 21:59:18